dan riebs wrote:

At the end of your Sport Aviation article,  you talk about
the difficulties of cooling a rotary, water-piston owners
are having the same problem.

1. Nobody uses water cooled engines because nobody else
does. Dumb, but true.
2. Bert Rutan told me he doesn't use water cooled engines
because they aren't reliable. I don't believe it.
3. The radiator induces tremendous drag, a valid complaint.

Instead of hanging a traditional radiator in the breeze, why

not integrate the oil, coolant, and turbocharger cooling
into the engine cowling? You'd get cooling anytime the
engine was running and the cooling induced drag would be
dramatically reduced.

1. EAA Experimenter published my letter on the subject and
said they didn't know why no one did this.
2. In the next issue a respondent suggested what I proposed
was the equivalent of building a bomb. I didn't feel like
telling him he had the same problem with a garden hose.
3. This used to be done using floats and leading edges
instead of the engine cowling on some of the old racing
seaplanes.

Nobody does this because no one else is doing it. Dumb, but
true. A few people have said they'd like to try it, if they
had time.

I am not sure I follow you here. Do you have surface rads
in mind? If so plenty of problems with those. 
Paul Lamar 

I've been told there are problems with the idea, what are
they?

Well if you are advocating using the cowling as a surface radiator
there is not enough surface area to achieve the necessary cooling.
Don't underestimate the surface area of an ordinary radiator.

Also this implies a metal cowl which is out of the question for most
home builts. Surface rads were also tried back in the early thirties and forties
and given up with just too many problems vis a vis leaks, excess weight
and inadequate surface area. The early P38 had intercoolers integrated
into the leading edges of the wings. They later switched to real
intercoolers to get better results and more HP.

Paul Lamar
 
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